Numerical investigation of the effect of wall-wetting on hydrocarbon emissions in engines

Steve T. Chin, Chia fon Lee

Research output: Contribution to conferencePaperpeer-review


The latest development of direct injection strategy for small gasoline and diesel engines produces significant wall-wetting. It becomes necessary to develop a better understanding of the relationship between wall-wetting and hydrocarbon (HC) emissions. To simulate these emissions from practical fuels, a multi-dimensional code for the spray and combustion was utilized. It included the spray/wall impingement model and the multi-component droplet and film vaporization model for gas and liquid phase transport processes. To extend these models to simulate combustion, a multi-component fuel combustion model was developed, which combined the rate constants for each of the fuel components on the basis of mole fraction to form an effective fuel. The effective fuel was then utilized to compute the reaction rates. The resulting models were then used to simulate the hydrocarbon emissions resulting from wall-wetting in gasoline engines. Qualitative comparisons between the computed and measured results were made. The agreement of both the overall trends and the transient history were reasonable. The computed results also provided significant insight to the causes of HC emissions. Wall-wetting location had a significant effect on HC emissions by allowing some of the unburned HC easy access to the exhaust, while making it nearly impossible for others to escape into the exhaust. The wetting of the cylinder liner underneath the exhaust valves arid the piston top led to large increases in HC emissions. Original is an abstract.

Original languageEnglish (US)
Number of pages1
StatePublished - 2002
Event29th International Symposium on Combustion - Sapporo, Japan
Duration: Jul 21 2002Jul 26 2002


Other29th International Symposium on Combustion

ASJC Scopus subject areas

  • General Engineering


Dive into the research topics of 'Numerical investigation of the effect of wall-wetting on hydrocarbon emissions in engines'. Together they form a unique fingerprint.

Cite this